Conversion of t4 to NDT

[Gwelos]

Hi, I am on 100 of Eltroxin and thinking of switching to NDT. I read in one of the posts that 1 grain is = to 75-100 of t4. Can anyone elaborate on that. 1 grain of NDT has 38 of t4 and I am at a loss to figure it out!

[SeasideSusie Remembering]

Gwelos 1grain NDT contains (generally) 38mcg T4 and 9mcg T3. 9 mcg T3 is roughly equivalent to 27mcg T4. So I grain is about roughly equivalent of 75mcg T4.

[Hidden in reply to SeasideSusie]

The T3 in Armour thyroid is stronger and PL says to multiply by 4 so your 9mcgs will = 36 mcgs

[SeasideSusie Remembering in reply to Hidden]

Who's PL please Hidden ?

I always thought you multiplied by 4, but someone else recently mentioned x 3. Is it just Armour where you multiply by 4 or is that generally?

Thanks

[Hidden in reply to SeasideSusie]

PL ...... Patient leaflet.

Mercury Pharma T3 liothyronine is usually x 3

But the patient leaflet of Armour thyroid is 38 mcgs T4 plus 9mcgs T3 which is x 4

I was rightfully told by my endo last year that changing from 1 1/2 grains Armour .. ...117 mcgs back to 75mcgs T4 plus 10 mcgs MP T3 ........117 1/2 mcgs would give me more T4 but less T3.

[SeasideSusie Remembering in reply to Hidden]

Thanks Hidden

PL - I never thought of that, I usually see Patient Information Leaflet, I though PL may be a manufacturer

So I was thinking along the right lines for synthetic T3 x 3, good to have confirmation.

I'm a bit puzzled about the Armour though. Just because it contains 38mcg T4 and 9mcg T3, how does that mean that the T3 is equivalent to x 4 T4. The way I see it is that the formula happens to contain those amounts of T4/T3, not that the T3 is 4 times as 'potent' as T4 - sorry, not a good explanation but my brain isn't functioning so well this time of night.

[Hidden in reply to SeasideSusie]

Hi Seaside Susie,

Have sat down tonight to send another reply to you as I really messed up with my info yesterday.Perhaps you can refer to my reply to helvella below. X

[helvella Administrator Thyroid UK in reply to Hidden]

Marfit74,

As all prescription-quality USA products (the RLC products, NP Acella and Armour) are made from the same Thyroid USP, supplied by the same sole supplier company, I am not sure that I understand what you are saying!

[Hidden in reply to helvella]

I have tried to explain to Seaside Susie above.

[helvella Administrator Thyroid UK in reply to Hidden]

I read that you were saying that the T3 in Armour is in some way stronger than the T3 in, say, Nature-Throid.

I agree that one and a half grains of Armour (at 57 micrograms) have less T4 than 75 micrograms of levothyroxine.

I agree that one and a half grains of Armour (at 13.5 micrograms) have more T3 than 10 micrograms of liothyronine.

I don't quite understand the rest - including the 117 number?

[Hidden in reply to helvella]

Firstly .....apologies for my mathematical efforts yesterday.I really messed up.

1 1/2grains Armour should = 111 ( 57+54 ) and my workings for T4/T3 were for 100/75 alternate days =

87 1/2 +30 = 117 1/2

Will have to excuse myself as being overtired ...... Took my husband to hospital this morning after a GP visit.He was suffering from fluid retention.His medications amongst others include Water tablets,Warfarin and 75 mcgs levo T4.He is being kept in for a couple of days to get rid of the excessive fluid......so sorry for him as also been having uncontrollable bleeds from nose and foot,to do with his warfarin.Just hoping they will now completely review his meds.......sorry for my previous unhelpful info.

[helvella Administrator Thyroid UK in reply to Hidden]

Ah! Right - everything makes much more sense. Sorry to have been unable to see what you had been doing there.

I think I'd have to say that when we get down to the finer details, the arithmetic actually gets less and less important. All the other issues such as timing, absorption, etc., start to be bigger factors than modest differences in numbers.

The "3 times" or "4 times" is very much an approximation. We all vary, and I suspect many of us vary by a bigger margin than this.

Hope your husband gets very much better, very soon. Sounds pretty unpleasant.

[Hidden in reply to helvella]

Thanks helvella.

[puncturedbicycle]

I found this very helpful as a rough guideline. Apparently it isn't uncommon to need slightly more ndt than you might have calculated against your synthetic meds.

centraldrugsrx.com/pdf/Thyr...

[Gwelos in reply to puncturedbicycle]

Thanks puncturedbicycle